The present invention relates to a harvesting machine for blueberries and other plants having an improved spoke-carrying mechanism which has an adjustable orbit and in which the spokes are adjustably inclined to the horizontal.
By way of background, blueberry harvesting machines are known wherein a spoke-carrying shaft is journalled for free rotation and is driven in an orbit so that the spokes jab in and out of blueberry bushes while they "walk" through the bushes as a result of the free rotation of the shaft. However, in the prior machine, there was no arrangement for adjusting the orbit of movement of the spoke-carrying shaft. Thus, the blueberry bushes were always subjected to the same amount of spoke thrust, although the speed of orbital movement could be changed.
I have discovered that successful harvesting depends on a combination of the speed and magnitude of orbital movement. Thus, for harvesting varieties of blueberries which are easily bruised, it is desirable to have a relatively small orbital movement and low speed. Other varieties can be harvested with a larger orbital stroke and low speed, and yet other varieties which are difficult to harvest may be subjected to relatively large orbital spoke movement and relatively high speeds. The ultimate objective is to remove as many ripe blueberries as gently as possible, while permitting the unripe berries to remain on the bushes for subsequent harvesting.
In addition, insofar as known, the spokes of prior blueberry harvesters were generally stacked in tiers, and they were generally parallel to each other. This only provided contact with a relatively small portion of the bush, and therefore berries on the bush which were located between the tiers of spokes, were generally not harvested to the fullest extent. It is with overcoming the foregoing deficiencies of the prior art that the present invention is concerned.